Accident Details
On September 13, 2009, at approximately 0915 eastern daylight time, a special light sport Flight Design GMBH CTSW, registration N466CT, was substantially damaged following a landing gear collapse after landing on runway 24 at Gettysburg Regional Airport (W05), Gettysburg, Pennsylvania. The certificated private pilot was not injured. Visual meteorological conditions prevailed for the local personal flight, which originated at W05 at 0830, and was conducted under Title 14 Code of Federal Regulations Part 91.
According to the pilot, he had completed some “air work” in the local flying area before returning for landing. During landing with a right crosswind of 5 to 6 knots and flaps set at 15 degrees, the right main landing gear touched first. When the left main gear touched down, the pilot heard a “thump,” the left gear collapsed, and the airplane veered off the side of the runway. On a scale of 1 to 10, the pilot described the landing as a “5” and stated that the left main landing gear’s contact with the runway was similar to that of the right.
Pilot Information
A review of Federal Aviation Administration (FAA) airman records showed that the pilot held a private pilot certificate with a rating for airplane single engine land. His most recent FAA third class medical certificate was issued October 9, 1985. The pilot’s most recent flight review was completed on April 18, 2008. The pilot reported 190 total hours of flight experience, with 70 hours in the accident airplane make and model.
Aircraft Information
According to FAA and maintenance records, the airplane was manufactured in 2007 and had accrued 90 total aircraft hours. Its most recent conditional inspection was completed on August 29, 2009, at 82 total aircraft hours.
Weather Conditions
The 0916 weather observation at Carroll County Airport (DMW), Westminster, Maryland, 19 miles southeast of the accident site, included clear skies and winds from 230 degrees at 6 knots. Visibility was 10 miles. Temperature was 24 degrees Celsius (24°C) and the dew point was 14 degrees Celsius (14°C). The altimeter setting was 30.01 inches of mercury.
Examination Findings
Examination of the airplane at the scene by an FAA inspector revealed separation of the left main landing gear and substantial damage to the fuselage at the attach point. The gear was retained for examination at the National Transportation Safety Board (NTSB) materials laboratory in Washington, D.C.
Data was downloaded from the Dynon Avionics D100 primary flight display for examination at the NTSB recorders laboratory. According to Dynon Avionics, the software version installed on the accident airplane "did not record data;" therefore, no accident flight data was recovered from the unit.
The left main landing gear attachment fitting was examined at the NTSB materials laboratory, and no preexisting fractures were noted. The fitting was manufactured as an all-steel weldment constructed from tubing and bar stock, which was powder-coated after fabrication. Examination revealed that the fitting failed due to overstress midway along the angled tube portion, and that the fractures were consistent with bending loads experienced during landing and taxiing. Examination further revealed that the wall thickness was less than the manufacturer's specification, and that the interior of the angled tube had been "counterbored" prior to powdercoating and final assembly.
Examination of the NTSB database revealed two additional accidents with identical damage and that in all three instances, the parts failed from an overstress fracture that initiated in approximately the same location.